REPORT OF THE GEOTECHNICAL INVESTI GATION FOR THE OF …

REPORT OF THE

GEOTECHNICAL INVESTIGATION FOR THE

OF THE PROPERTY AT 2266 LAKESHORE ROAD WEST & 83 EAST STREET

OAKVILLE, ONTARIO

Prepared for

Symgine (Lake East) Inc.

Acting on instructions received from Mike Petrovsky

Our Reference number 14-1433 February 17, 2015

Table of Contents 1.0 INTRODUCTION .............................................................................................................................................. 1

2.0 SITE GEOLOGY ............................................................................................................................................... 2

3.0 FIELD AND LABORATORY WORK........................................................................................................ 2

4.0 SUBSURFACE CONDITIONS .................................................................................................................... 3

5.0 GEOTECHNICAL DISCUSSIONS ............................................................................................................ 4 5.1 BEARING CAPACITY, FOUNDATIONS AND SETTLEMENT ................................................................................... 4 5.2 SLAB-ON-GRADE ............................................................................................................................................. 4 5.3 EXCAVATION AND BACKFILL ........................................................................................................................... 5 5.4 DEWATERING AND DRAINAGE CONSIDERATIONS ............................................................................................ 5 5.5 BASEMENT WALLS ........................................................................................................................................... 6 5.6 EARTHQUAKE CONSIDERATIONS ...................................................................................................................... 6 5.7 ASPHALT CONCRETE PAVEMENTS ................................................................................................................... 7 5.8 SHORING DESIGN CONSIDERATIONS ................................................................................................................ 8

6.0 LIMITATIONS ................................................................................................................................................ 11

7.0 CLOSURE ........................................................................................................................................................ 12

Appendix A Typical Grain Size Distribution Curve of Soil Overburden B Test Hole Location Plan and Borehole Records

2266 Lakeshore Road West & 83 East Street, Oakville Candec Engineering Consultants Inc.

February 17, 2015

February 17, 2015 Symgine (Lake East) Inc. 229 - 6021 Yonge St Toronto, Ontario M2M 3W2 Attention: Mr. Mike Petrovsky Dear Sir; Re: Proposed Residential Development

2266 Lakeshore Road West & 83 East Street, Oakville Our Reference Number: 14-1433 1.0 INTRODUCTION Candec Engineering Consultants Inc. (Candec) has carried out a geotechnical investigation of the above referenced property that is proposed as the site of a new residential development. The purpose of the investigation was to determine the subsoil conditions and to provide recommendations pertaining to the geotechnical aspects of the buildings that are likely to be constructed at the property. At the time the investigation was carried out, the details of the development were not known, however it is assumed that possibly a highrise building, similar to those in existence in the area will be constructed and that there may be one or more four levels of basement to be used for parking and common element amenities. The exterior landscaping is slated to be a combination of soft and hard surfaces, along with outdoor recreational facilities.

2266 lakeshore Road West & 83 East Street, Oakville Geotechnical Investigation February 17, 2015

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It is assumed that the design will comply with the applicable codes and standards. This report presents the results of the investigation performed in accordance with the general terms of reference outlined above. No portion of this report should be used as a separate entity. It should be clearly understood that the report is written to be read in its entirety. It should be noted that we have also carried out geotechnical investigations within the immediate vicinity of this site, and have extracted the information in our files and relied on our expertise in this regard in the execution of this investigation. 2.0 SITE GEOLOGY Globally, the ground surface slopes downward to the south and west. Hydraulically, it is expected that the groundwater regime will also slope down to the south. Given that the soil is expected to be predominantly fine grained and cohesive. As such, it is expected that the vertical and horizontal permeability and percolation rates will be relatively low, likely less than 1x10-3 cm/sec. The geology is expected to be characterized by Halton Till (Ontario – Erie Lobe). This deposit is predominantly a silt and silty clay matrix. The soil matrix is underlain by Upper Ordovician shale, limestone, dolostone and siltstone of the Queenston Formation. Bedrock is expected to be located at a depth of approximately 3m to 10m below the ground surface. 3.0 FIELD AND LABORATORY WORK The fieldwork was comprised of 4 boreholes drilled to auger refusal on intact shale bedrock, and 2 testpits, excavated to shale in order to better observe possible groundwater infiltration Together, the locations of the test holes are detailed in Drawing No. 1. The drilling, sampling and excavation were carried out by a specialist soil drilling contractor under the direction of personnel from Candec, who logged the boreholes in the field and transported the extracted soil samples to our laboratory for testing.

Candec Engineering Consultants Inc.


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The boreholes were advanced using continuous flight augers. The subsurface strata were sampled at regular intervals of depth using a split-spoon sampler and following the procedure detailed in the ASTM standard specification D1586 for the Standard Penetration Test. The coring of the bedrock was achieved by using a BX standard double tube core barrel. None of the boreholes were instrumented as monitoring wells, but water level observations were made in each borehole upon its completion and as well as in the test pits for a few hours after completion in order to evaluate the groundwater regime across the site. A summary of the results of the field and laboratory tests is detailed on the borehole records are presented in the appendix of this report. 4.0 SUBSURFACE CONDITIONS No fill material was encountered in any of the boreholes. The undisturbed soil strata are situated immediately below the pavement or topsoil veneer. It is comprised of layers of brown sandy silt with clay, sandy silt and silt tills. The soil strata interface with shale bedrock at depths that range from 2.2 to 3.5m across the site. In general, the shale interface is at a depth of 2.5m. The undisturbed soil generally is moist, and has a dense to very dense insitu consistency. The standard penetration test N-values that were recorded in the soil generally ranged from 20 blows to refusal (greater than 60 blows required for 150mm of penetration). Occasionally an obstruction was encountered that prevented the auger from being advanced. The indications are that these obstructions were shale fragments. The insitu moisture content of the sandy silt soil generally was between 9% and 12%. Groundwater was not encountered in any of the test holes.



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5.0 GEOTECHNICAL DISCUSSIONS 5.1 Bearing Capacity, Foundations and Settlement A combination of spread and strip footings can be used to support the footings for the high rise buildings and the parking garage. It is anticipated that the footings will be founded on shale. It is the recommended that these footings should be designed using the bearing pressures detailed in the table below.

Bearing pressure for settlement (SLS)/Factored Ultimate Soil Bearing Pressure (ULS) and Corresponding Founding Level

Depth (m)

SLS (KPa)

ULS (KPa)

3 – 8 2,500 5,000 The estimated maximum total settlement for these footings is 25mm, and the estimated maximum differential settlement relative to the spread and strip footings is 15mm. The bases of the foundation excavations must be inspected by a geotechnical engineer in accordance with the stipulations in the Ontario Building Code to confirm the bearing capacity of the subsoil. The clean on-site soil can be used as engineering fill. It should be compacted to 100% of the standard Proctor maximum dry density. The bearing capacity that will be attained is 150Kpa. 5.2 Slab-On-Grade Slab-on-grade construction may be employed at this site. The expectation is that slab on grade for the building will be founded on a shale subgrade. Therefore, no proof compaction will be needed. It is imperative that the slabs sit either completely on soil or on shale to ensure that differential movement does not occur.



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It is recommended that the slab-on-grade should be constructed on a layer of 19mm clean crushed stone that is at least 150mm thick. 5.3 Excavation and Backfill Excavation of the soil over burden at this site will be achieved easily using a crawler excavator. The same equipment should be capable of excavating the shale necessary to achieve the desired foundation horizons, but with a pneumatic ripper attachment as needed to dislodge any limestone inclusion that might be encountered. The on-site soil overburden soil can be used as fill. It should be noted that it is fine grained, and it will be difficult to achieve satisfactory levels of compaction in the event its moisture content exceeds its optimum value by more than 3 percentage points. Either a sheepsfoot or a smooth drum roller non-vibratory can be used to compact the soil in order for best results to be achieved. The soil is silty material and as such it may become dilatant and loose its strength when saturated and agitated. It also contains a significant proportion of fine sand that will make it especially frost susceptible. In the latter regard, adequate soil cover must be provided for footings that are founded in mineral soil. The sides of open cut excavations can be sloped to 4:1 to ensure that any sloughing that is caused by intermittent seepage from the seams located in the walls of the excavation does not precipitate slope instability. We are of the opinion that in the event open cut excavations will be created at the site for the purposes of construction, the sides of the excavation should be covered with a reinforced geogrid or they should be shotcreted. The slopes of all sides of the excavations must be monitored at least every other day visually, by an experienced geotechnical engineer, during construction for as long as the excavations remain open in order to secure timely indications of potential slippage, popping or instability. 5.4 Dewatering and Drainage Considerations Ground water was not encountered in any of the boreholes or testpits that were put down during the course of the investigation.



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Nevertheless, we are of the opinion that a perimeter drainage system will be required in the event there are subsurface habitable spaces including basement parking. The permanent drainage system should be comprised of a combination a sheet drain where there is shoring, and freely draining gravel backfill where there is an open cut. Extensive dewatering facilities will not be needed during construction. However, some allowance should be made to collect and dispose of surface runoff water that collects in the excavation made for construction. It is expected that mostly these will comprise pumps placed in strategically located sumps. The volume of water is likely to be dictated by the volume of precipitation rather than the groundwater that may intermittently seep into the excavation. 5.5 Basement Walls The subsurface walls of the structures should be designed to resist an earth pressure, 'p', at any depth, 'h', evaluated using the expression:

P = k (γh + q) where k = 0.35, is the estimated applicable earth pressure

coefficient;

γ = 22.1KN/m3, the average unit weight of the soil/rock behind the wall;

q = is an allowance for surface surcharge, if any.

It is assumed that the backfill adjacent to the walls will be freely draining material so as to prevent the build up of pore pressure behind the wall. This is an OBC requirement. 5.6 Earthquake Considerations The subsoil profile at the property is comprised predominantly of shale bedrock, and the building foundations will rest on shale. The RQD values that were calculated based on the core recovery and condition data collated by AMEC indicates that at the likely depths at which the foundations will be constructed, the rock is classified and medium



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to good quality and hard. Therefore, the site classification for seismic site response is ‘B’, and should be used in relation to the earthquake resistant design aspect of the buildings. 5.7 Asphalt Concrete Pavements The existing natural undisturbed soil profile will be capable of supporting flexible pavement structures. The following modulii of subgrade reaction were estimated from the standard penetration test N-values that were registered during the drilling and sampling program;

Depth (mm) K (Mpa/m) 300 31.0 450 42.0

In order to achieve these values, all deleterious materials (topsoil) that are encountered must be stripped from the areas in which a pavement is to be constructed. All deleterious materials that are encountered must be stripped from the areas in which an asphalt concrete pavement is to be constructed on the native soil profile or on engineered fill. The exposed subgrade should be subjected to proof rolling (4 to 6 passes by a large non-vibratory roller) in the presence of a geotechnical engineer. It should also be compacted to a minimum of 98% of the SPMDD. The paved roadways should be shaped and crowned to provide drainage. Provided this will be done, and all excavations for the sewer and buried utilities are backfilled and compacted to a dense state, the minimum pavement thicknesses detailed in the table below are recommended. The asphalt concrete cover may be made up of a base coat comprised of HL-8 asphalt concrete covered with a 50mm thick surface course of HL-3 asphalt concrete where the total thickness is to be greater than 50mm. The materials comprising the base and sub-base courses should be compacted to a minimum 100% of their standard Proctor density. The materials comprising the asphalt



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concrete courses should be compacted to a minimum 96% of their Marshall density. In the event the pavement will be constructed on the parking garage roof deck, the sub-base granular layer will not be needed. The pavement surfaces should be sloped to channel surface runoff water to strategically placed catchbasins that should be connected to the storm sewer system. Some consideration should be given to placing 100mm or 150mm high strip drains (for example Terradrain made by Terrafix Geosynthetics Inc.) behind the concrete curbs in order to prevent the accumulation of water behind the curbs and under the pavement . These drains should also be connected to the sewer system. It is recommended that the concrete curbs that are slated for construction on the native soil profile should be cast directly on the subsoil and not on the granular course in order to prevent water from the landscaped areas migrating under the pavement.

Minimum Pavement Thickness

Description Car Parking Areas (Light

Duty)

Driveways (Heavy Duty) Materials

Asphalt Cover 50mm 100mm Hot mix asphalt

Base Course 200mm 150mm 19mm crushed limestone or Granular “A”

Sub-base Course - 300mm Granular “B”

5.8 Shoring Design Considerations The shoring design should be performed by a specialist engineering consultant. The following sets out basis parameters and a design approach based on the procedure detailed in the Canadian Foundation Engineering Manual, 4th edition. It is assumed that the excavation could extend to a depth of 8.0m. Therefore, one level of tie back supports should be adequate.



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It may also be possible to eliminate the need for lateral supports by utilising cantilevered soldier piles depending on the depth of the excavation. The active earth pressure at any depth, H, per unit length of the excavation wall can be estimated by the expression:

PA = KA ( γ H + q) where

γ = the unit weight of the soil being retained = 21 KN/m3 H = depth of excavation (m)

q = equivalent uniform vertical pressure of any surcharge adjacent to the

excavation KA = active earth pressure coefficient

= 0.4, where adjacent building footings or buried services fall within an envelope formed by a 60m line drawn from the base of the excavation wall to the ground surface.

= 0.3 where adjacent building footings or buried services fall outside

an envelope formed by a 60m line drawn from the base of the excavation wall to the ground surface.

= 0.23 where adjacent building footings or buried services are outside an envelope formed by a 45° line drawn from the base of the excavation

wall to the ground surface. In order to achieve more positive support from the shoring system, a rectangular earth pressure distribution should be assumed. This expression assumes that the soil immediately behind the lagging boards is comprised of freely draining material at least to the level of the base of the excavation. The passive earth pressure resistance developed by the soil in front of the buried portion of the buried portion of the soldier pile can be estimated using the following parameters

FP = the factor of safety for embedment of soldier piles



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= 2.0

KP = passive earth pressure coefficient = 5.0

N = influence factor = 2.0

B = diameter of the soldier piles

γ = unit weight of the soil

= 21 kN/m3

d = depth of embedment below the base of the excavation or below the founding level of an adjacent footing, whichever is lower (m)

τ = shear strength of the rock, 0.8MPa

The thickness of the lagging boards to be used is dependent on the spacing of the soldier piles. Recent experience at construction sites within the Metropolitan Toronto area suggests the following:

Pile Spacing (m) Lagging Board Thickness (mm)

2.5

76

3.0

100

It should be noted that the lateral movement of the shoring system must be monitored especially at locations in which settlement sensitive structures are present. These measurements are required not only to ascertain the stability of the shoring but also to identify any movement that may influence the thickness of the exterior subsurface walls of the proposed structure.



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6.0 LIMITATIONS The report is limited in scope to those items specifically referenced in the text. No other testing and design calculations have been performed except as specifically reported. It should be understood that the data we have collated and the opinions we have formed after reviewing this information should not be construed as a guarantee but only a guide to probable expectations. Conditions that exist but are not recorded herein were not apparent given the level of study authorised. The discussions and recommendations presented in this report are intended for the sole guidance of the client named along with their architectural and structural design consultants. It should not be relied upon for any other purpose. Unauthorised parties who use this report do so totally at their own risk. The information on which the recommendations stated herein are based is subject to confirmation by engineering personnel from Candec at the time of construction. The fact that localised variations in the subsurface conditions may be present between and beyond the boreholes and that those conditions may be significantly different from the general description provided for design purposes should be understood. This applies particularly to the thickness and consistency of the soil strata. Contractors should make their own interpretation of the factual borehole and sample test results detailed in this report or contact us for assistance, and should draw their own conclusions as to the effect of subsurface conditions on work below ground level. It is strongly urged that Candec be contacted to provide assistance in the interpretation of the borehole records by anyone undertaking work on or below the ground surface at this site prior to this work being carried out.



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7.0 CLOSURE The report that has been prepared is predicated on our understanding of the proposed plan of development. In the event the plan is changed, it may be necessary to review and revise some of the recommendations we have set out herein. In addition, it is essential that you communicate any alternative design schemes that you are contemplating so that we can give our opinion on the geotechnical implications. We trust that this report satisfies your requirements at this time. Please do not hesitate to call us in the event we can be of further service. Yours truly, CANDEC ENGINEERING CONSULTANTS INC. Bernard Moore, P. Eng., M. Eng. Principal BFM/ :\LakeshoreRoadWest@EastSt\geo rpt-Feb17.doc


Appendix A

Typical Particle Size Gradation Curve


February 17, 2015


February 17, 2015

Appendix B

Borehole Location Plan &

Borehole Logs


February 17, 2015

Test Hole Location Plan

BH-1

BH-4

BH-3

BH-2

TP-1 TP-2


February 17, 2015

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